Push-rod latch for air brakes



Nov. 22,` 1927.y 1,649,801

H. F. BlcKEL PUSH HOD LATCH FOR AIR BRAKES Filed Aug. 51, 1926 @Mag Patented Nov. 22, 1927.

UNITED STATES ineen PATENT OFFICE.

HENRY F. BICKEL, OF PLAINFIELD, NEW' JERSEY, ASSIGNOR TO NEW YORK AIR BRAKE CGMFANY, A. CORPORATON OF NETN JERSEY.

IPUSIIVROD-LATCH FOR AIR BRAKES.

Application lediAugust 31, 1926. y Serial No. 132,811.

This invention relates to air brakes, and particularly to a latching mechanisui for connecting;` a bralre cylinder piston in thrust relation `with the brake rigging, after another brale cylinder piston has taken up the slaclr. f

Many two-cylinder brake systems have been proposed iu which one cylinder tralies up the slack, whereupon a second cylinder is rendered active, is latohcd to the brake rigging' and becomes eicctive in the application of the brakes with a minimum piston travel. The usual method of latching the brake cylinder to the brake vrigging` is to allow the push rod of the auxiliary cylinder to be drawn outward through the tubular piston rod as the slack is taken up, and as soon as the piston rod starts to move outward a latch rendered effective by such motion establishes a connection between the piston rod and the push rod.

The present invention relates vtov the construction of such a latch, and the object of the invention is to provide a form of latch which will permit angular and lateral motion of the push rod relatively to the tubular piston rod without affecting' the engagement of the latch or the ability of the latch to engage initially.

This result is accomplished by supporting` the latch in such a way that it is capable of universal angular motion and also of lateral sliding` motion relatively to the tubular piston rod7 both such motions being son'iewhat limited in extent, but adequate to meet the requirements of service.

A preferred embodiment of the invention is illustrated in the accompanying drawings, in which- Figure 1 is a diagrammatic view showing main and auxiliary brake cylinders and their connection to the foundation brake gear according-1,' to the present invention.

F igure 2 is a longitudinal axial section through the outer end of the piston rod guide'and the piston rod of the auxiliary cylinder showing the improved latch applied. In this view the piston rod is shown retracted in the position assumed during' release and until the auxiliary brake cylinder commences to function.

Figure 8 is a similar view showing the parts in the position assumed after the auxiliary piston rod has started its outward motion.

F injure d is a section on the line Ll--t of Fig. 2.

Figure 5 element. i

Figure 6 isa section thereof on `the 6 6 of Figure 5.

The main brake cylinder is shown at 11 and of course is supported on the car frame. rlheusual tubular piston rod is shown at 12 and the push rod at 18. It will be understood that as is usual the push` rod 18 enters the piston rod 12 and is in thrust relation therewith at its inner end adjacent the pisis adetail elevation of the latch line ton. i This is standard construction in the art.

One brake lever is shown` at 14 .and is fulcrumed at 15 to the head of the cylinder 11. 1t is also pinned at' 16 to the brake rod 17. The other brake lever 18 is pinned at 19 to the push rod 13 and at 20 to the brake rod 21. Levers 14 and 18 are connected by the usual connecting rod 22 which is pinned to them at 28 and 241' respectively. The brake lever 18 extends beyond the pivot pin 19 and is pinned at 25 tothe push rod 2G which extends loosely into the giston rod 27 of the auxiliary brake cylinder 28. The piston rod guide of the cylinder 28 is formed with an extension or lug 29which acts as a disengaging stop for the latch about to be described when the auxiliary piston is in its fully retracted position.

Various valve mechanisms have heretofore been proposed controlling` two such cylinders as 11 and 28 in such mannerthat'a-ir is iirst admitted to the cylinder 11 to take up the slack in the brake rigging. In such action the push rod 26 moves outward through the piston rod 27 of the auxiliary cylinder 28, the piston of the cylinder 28 remaining` in its retracted position. As soon as the slack has been taken up air is admitted to the cylinder 28. forcing;- out its pistou rod 27. The initial outward motion of the piston rod causes this rod to latch to the push rod 26.

Latch mechanisms for accomplishing this function have heretofore been known, but they have not worked satisfactorily in all cases, and I have discovered that one contributing' causo of such improper actuation is that the push rod 26 necessarily has angular andlateral motions relatively to the pistonrod 27 and the latch mechanisms heretofore used have not been adapted to accommod'ate themselves to such motions. The

mism1 Clesghefd `fo velcomoth T- The combination with a tubular piston A Collar 30 is threaded on The fo1'WaL'd.4lnd.-rodund a` mother push rofl loosely xrlounted It i@ formed th1ein,of a latch 'for connecting; the two;

a. cylindrical recess 33 V21 pu 32 in, one `,end of tl 

